configure: Copy test data to build directory

The QDict unit-tests (check-qdict) will fail when ran on a different
build directory. That's, it only works when ran on the source dir.

This happens because its data file (qdict-test-data.txt) is not
copied to the build dir. Fix it.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>

configure

@@ -3614,7 +3614,7 @@ DIRS="$DIRS roms/seabios roms/vgabios"
 DIRS="$DIRS fsdev ui"
 DIRS="$DIRS qapi"
 DIRS="$DIRS qga trace"
-FILES="Makefile tests/Makefile"
+FILES="Makefile tests/Makefile qdict-test-data.txt"
 FILES="$FILES tests/cris/Makefile tests/cris/.gdbinit"
 FILES="$FILES pc-bios/optionrom/Makefile pc-bios/keymaps"
 FILES="$FILES pc-bios/spapr-rtas/Makefile"